The present invention relates to an apparatus for separating impurities, such as dust, dirt and the like, from fiber material, particularly cotton, the apparatus including a clothed roller disposed behind a feeding device for gripping and further transporting the fiber material. In apparatus of this type, a condenser serves to effect a separation of air and cotton at the end of a tubular conduit. It has been found that this simultaneously removes dust from the cotton.
The major components of any condenser are a fan and a screen drum, the latter rotating so as to continuously offer a new screen surface to the stream of air laden with cotton. The lap or cotton wool collected on the screen drum must then be removed again immediately from the drum so that the screen surfaces remain fully receptive. The condenser has three openings: one for the influx of the material to be cleaned; one for removal of the cleaned cotton; and one for the removal of the air and the dust.
Suction is produced within the drum so that the fiber material is pulled to the outer jacket of the drum where the lap is formed. The suction pull imparts a certain increase in density to the web so that dust removal is made more difficult.